Disc brake caliper and disc brake caliper assembly

ABSTRACT

A disc brake caliper for applying a braking force on a brake disc rotor configured to be rotatable about a rotational axis. The disc brake caliper comprises an attachment surface and a first threaded hole. The attachment surface is configured to face a pipe portion of a bicycle frame in a state where the disc brake caliper is coupled to the bicycle frame. A first thread bolt is to be inserted in the first threaded hole so as to couple the disc brake caliper to one of the bicycle frame and a base member attached to the bicycle frame, the first threaded hole being provided on the attachment surface.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of the U.S. patentapplication Ser. No. 14/284,343 filed May 21, 2014 that issued as U.S.Pat. No. 9,533,733, which is a continuation-in-part application of theU.S. patent application Ser. No. 13/931,027 filed Jun. 28, 2013 thatissued as U.S. Pat. No. 9,227,691. The contents of these applicationsare incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a disc brake caliper and a disc brakecaliper assembly.

Discussion of the Background

Bicycling is becoming an increasingly more popular form of recreation aswell as a means of transportation. Moreover, bicycling has become a verypopular competitive sport for both amateurs and professionals. Whetherthe bicycle is used for recreation, transportation or competition, thebicycle industry is constantly improving the various components of thebicycle. One component that has been extensively redesigned is thebicycle brake device. In particular, in recent years, bicycles have beenprovided with disc braking devices.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the present invention, a disc brakecaliper for applying a braking force on a brake disc rotor configured tobe rotatable about a rotational axis. The disc brake caliper comprisesan attachment surface and a first threaded hole. The attachment surfaceis configured to face a pipe portion of a bicycle frame in a state wherethe disc brake caliper is coupled to the bicycle frame. A first threadbolt is to be inserted in the first threaded hole so as to couple thedisc brake caliper to one of the bicycle frame and a base memberattached to the bicycle frame, the first threaded hole being provided onthe attachment surface.

In accordance with a second aspect of the present invention, the discbrake caliper according to the first aspect is configured so that thefirst threaded hole has a first center axis which is non-parallel to therotational axis in a state where the disc brake caliper is mounted tothe bicycle frame.

In accordance with a third aspect of the present invention, the discbrake caliper according to the second aspect is configured so that thefirst center axis is parallel to a braking plane which is perpendicularto the rotational axis in a state where the disc brake caliper ismounted to the bicycle frame.

In accordance with a fourth aspect of the present invention, the discbrake caliper according to the first aspect further comprises a secondthreaded hole in which a second thread bolt is to be inserted so as tocouple the disc brake caliper to one of the bicycle frame and the basemember, the second threaded hole being provided on the attachmentsurface.

In accordance with a fifth aspect of the present invention, the discbrake caliper according to the fourth aspect is configured so that theattachment surface defines an end surface which faces the pipe portionof the bicycle frame.

In accordance with a sixth aspect of the present invention, the discbrake caliper according to the fourth aspect is configured so that theattachment surface comprises a single flat surface on which the firstthreaded hole and the second threaded hole are provided.

In accordance with a seventh aspect of the present invention, the discbrake caliper according to the fourth aspect is configured so that theattachment surface comprises a first portion and a second portiondivided from the first portion. The first threaded hole is provided onthe first portion of the attachment surface and the second threaded holeis provided on the second portion of the attachment surface.

In accordance with an eighth aspect of the present invention, the discbrake caliper according to the fourth aspect is configured so that thefirst threaded hole has a first inner diameter. The second threaded holehas a second inner diameter equal to the first inner diameter.

In accordance with a ninth aspect of the present invention, the discbrake caliper according to the fourth aspect is configured so that thefirst threaded hole has a first center axis which is non-parallel to therotational axis in a state where the disc brake caliper is mounted tothe pipe portion of the bicycle frame.

In accordance with a tenth aspect of the present invention, the discbrake caliper according to the ninth aspect is configured so that thefirst center axis is parallel to a braking plane which is perpendicularto the rotational axis in a state where the disc brake caliper ismounted to the bicycle frame.

In accordance with an eleventh aspect of the present invention, the discbrake caliper according to the tenth aspect is configured so that thesecond threaded hole has a second center axis parallel to the firstcenter axis.

In accordance with a twelfth aspect of the present invention, the discbrake caliper according to the fourth aspect further comprises a firstpiston. The first threaded hole has a first center axis. The secondthreaded hole has a second center axis. The first piston is disposedbetween the first center axis and the second center axis.

In accordance with a thirteenth aspect of the present invention, thedisc brake caliper according to the twelfth aspect further comprises asecond piston disposed between the first center axis and the secondcenter axis so as to at least partially face the first piston.

In accordance with a fourteenth aspect of the present invention, thedisc brake caliper according to the thirteenth aspect is configured sothat the first center axis is non-parallel to the rotational axis in astate where the disc brake caliper is mounted to the pipe portion of thebicycle frame.

In accordance with a fifteenth aspect of the present invention, the discbrake caliper according to the fourteenth aspect is configured so thatthe first center axis is parallel to a braking plane which isperpendicular to the rotational axis in a state where the disc brakecaliper is mounted to the bicycle frame.

In accordance with a sixteenth aspect of the present invention, the discbrake caliper according to the fifteenth aspect is configured so thatthe second center axis is parallel to the first center axis.

In accordance with a seventeenth aspect of the present invention, a discbrake caliper comprises a first piston and a first threaded hole. Thefirst piston is configured to be movable in a movement direction. Afirst thread bolt is to be inserted in the first threaded hole so as tocouple the disc brake caliper to one of the bicycle frame and a basemember attached to the bicycle frame. The first threaded hole has afirst center axis non-parallel to the movement direction.

In accordance with an eighteenth aspect of the present invention, thedisc brake caliper according to the seventeenth aspect is configured sothat the first center axis is parallel to a braking plane which isperpendicular to the movement direction.

In accordance with a nineteenth aspect of the present invention, thedisc brake caliper according to the seventeenth aspect further comprisesa second threaded hole in which a second thread bolt is to be insertedso as to couple the disc brake caliper to one of the bicycle frame andthe base member, the second threaded hole having a second center axisnon-parallel to the movement direction.

In accordance with a twentieth aspect of the present invention, the discbrake caliper according to the nineteenth aspect is configured so thatthe first threaded hole has a first inner diameter. The second threadedhole has a second inner diameter equal to the first inner diameter.

In accordance with a twenty-first aspect of the present invention, thedisc brake caliper according to the nineteenth aspect is configured sothat the first piston is disposed between the first center axis and thesecond center axis.

In accordance with a twenty-second aspect of the present invention, thedisc brake caliper according to the twenty-first aspect furthercomprises a second piston configured to be movable in the movementdirection and disposed between the first center axis and the secondcenter axis so as to at least partially face the first piston.

In accordance with a twenty-third aspect of the present invention, thedisc brake caliper according to the twenty-second aspect is configuredso that the first center axis is parallel to a braking plane which isperpendicular to the movement direction.

In accordance with a twenty-fourth aspect of the present invention, thedisc brake caliper according to the twenty-third aspect is configured sothat the second center axis is parallel to the first center axis.

In accordance with a twenty-fifth aspect of the present invention, adisc brake caliper assembly comprises the disc brake caliper accordingto any one of the first to twenty-fourth aspects, a base member, and afirst thread bolt. The base member is configured to be coupled to thedisc brake caliper and to be attached to the pipe portion of the bicycleframe. The first thread bolt is configured to be inserted to the firstthreaded hole via the base member so as to couple the base member to thedisc brake caliper.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a left side elevational view of a front portion of a bicyclewith a disc brake caliper assembly in accordance with a firstembodiment;

FIG. 2 is a partial side elevational view of a disc brake device withthe disc brake caliper assembly in accordance with the first embodiment;

FIG. 3 is a schematic structural diagram of the disc brake deviceillustrated in FIG. 2;

FIG. 4 is an exploded perspective view of the disc brake caliperassembly illustrated in FIG. 2 (first position);

FIG. 5 is an exploded perspective view of the disc brake caliperassembly illustrated in FIG. 2 (first position);

FIG. 6A is a back view of a base member illustrated in FIG. 5;

FIG. 6B is a partial cross sectional view of the base member taken alongline VIB-VIB of FIG. 6C;

FIG. 6C is a front view of the base member illustrated in FIG. 5;

FIG. 7 is an exploded perspective view of the disc brake caliperassembly illustrated in FIG. 2 (second position);

FIG. 8A is an elevational view of the disc brake caliper assemblyillustrated in FIG. 4 (first position);

FIG. 8B is an elevational view of the disc brake caliper assemblyillustrated in FIG. 7 (second position);

FIG. 9 is a perspective view of a disc brake caliper assembly inaccordance with a second embodiment;

FIG. 10 is a cross-sectional view a disc brake caliper of the disc brakecaliper assembly illustrated in FIG. 9;

FIG. 11 is an exploded perspective view of the disc brake caliperassembly illustrated in FIG. 9;

FIG. 12 is an exploded perspective view of the disc brake caliperassembly illustrated in FIG. 9; and

FIG. 13 is a cross-sectional view the disc brake caliper illustrated inFIG. 9.

DESCRIPTION OF THE EMBODIMENTS

The embodiments will now be described with reference to the accompanyingdrawings, wherein like reference numerals designate corresponding oridentical elements throughout the various drawings.

First Embodiment

Referring initially to FIG. 1, a bicycle 10 includes a bicycle frame 14,a front wheel 17, a rear wheel (not shown), a drive train (not shown),and a disc brake device 12. The bicycle frame 14 includes a main frame13 and a pipe portion 40. In the illustrated embodiment, the pipeportion 40 is a part of a front fork. The pipe portion 40 can, however,be bicycle parts other than the front fork. The front wheel 17 isrotatably supported by the front fork. A handlebar 15 (FIG. 2) isattached to a front fork column by a stem. The rear wheel is rotatablysupported by a rear end of the main frame 13. The disc brake device 12includes a disc brake caliper assembly 100, a brake disc rotor 50, and abrake operating mechanism 16.

In the present application, the following directional terms “front”,“rear”, “forward”, “rearward”, “left”, “right”, “upward” and “downward”as well as any other similar directional terms refer to those directionswhich are determined on the basis of the rider who sits on a saddle (notshown) of a bicycle with facing the handlebar 15. Accordingly, theseterms, as utilized to describe the disc brake caliper assembly 100should be interpreted relative to a bicycle equipped with the disc brakecaliper assembly 100 as used in an upright riding position on ahorizontal surface.

Referring to FIG. 2, the disc brake caliper assembly 100 is mounted tothe pipe portion 40 of the bicycle frame 14. It should be understoodthat the disc brake caliper assembly 100 can be mounted to the mainframe 13 for the rear wheel. The disc brake caliper assembly 100comprises a disc brake caliper 110 and a base member 120. The disc brakecaliper assembly 100 is also referred to as a bicycle brake caliperassembly 100 hereinafter. The disc brake caliper 110 is also referred toas a brake caliper 110 hereinafter. The brake caliper 110 is coupled tothe base member 120. The base member 120 is attached to the pipe portion40 by a first attaching member 151 and a second attaching member 155.The brake operating mechanism 16 is designed to actuate the bicyclebrake caliper assembly 100 to apply a braking force on the brake discrotor 50. The brake disc rotor 50 is mounted on a front hub shell 60 tobe integrally rotatable with the front hub shell 60 and the front wheel17 (FIG. 1) about a rotational axis A1. Brake disc rotors havingdifferent outer diameters can be mounted on the front hub shell 60. Thebicycle brake caliper assembly 100 is so configured that relativeposition between the rotational axis A1 and the brake caliper 110 isadjustable in a radial direction D1 of the brake disc rotor 50.

As seen FIG. 2, the brake operating mechanism 16 includes a mastercylinder 24, a master piston 34, a clamp 26, a brake lever 28, and ahydraulic fluid reservoir 36. The brake operating mechanism 16 ismounted on the handlebar 15 via the clamp 26. The master cylinder 24includes a master cylinder bore 32 in which the master piston 34 ismovably disposed. The brake lever 28 is pivotally coupled to the mastercylinder 24 for operating the bicycle brake caliper assembly 100. Thebrake lever 28 is operatively coupled to the master piston 34 such thatthe master piston 34 is movable in the master cylinder bore 32 inresponse to the pivotal movement of the brake lever 28. The hydraulicfluid reservoir 36 is in fluid communication with the master cylinderbore 32. The master cylinder 24 and the hydraulic fluid reservoir 36contain hydraulic fluid such as mineral oil. The master cylinder 24 hasan outlet port 38 for supplying hydraulic fluid to the bicycle brakecaliper assembly 100 via a hydraulic brake hose 86 and a banjo 87.

Referring to FIG. 3, the disc brake caliper 110 is for applying abraking force on the brake disc rotor 50 configured to be rotatableabout the rotational axis A1. The disc brake caliper 110 furthercomprises a housing 112, a first piston 74, a second piston 75, and apair of brake pads 76. The brake pads 76 are biased by a biasing member(not shown) toward the first and second pistons 74 and 75. The first andsecond pistons 74 and 75 are arranged to press the brake pads 76 towardthe brake disc rotor 50. The housing 112 includes a pair of cylinders57, and a caliper fluid passage 58. The first piston 74 is configured tobe movable in a movement direction D4. The second piston 75 isconfigured to be movable in the movement direction D4. The first andsecond pistons 74 and 75 are disposed within the cylinders 57 to bemovable in an axial direction D2 of the brake disc rotor 50. Themovement direction D4 is substantially parallel to the axial directionD2 in a state where the disc brake caliper 110 is mounted to the bicycleframe 14 (FIG. 2). The fluid chambers 59 are defined by the first andsecond pistons 74 and 75 and the cylinders 57. The fluid chambers 59 arein fluid communication with the caliper fluid passage 58. The caliperfluid passage 58 is in fluid communication with the master cylinder 24via the hydraulic brake hose 86.

When the brake lever 28 is operated, the master piston 34 moves withinthe master cylinder 24 in response to the pivotal movement of the brakelever 28, which allows pressure fluid to move through the hydraulicbrake hose 86 connected to the brake caliper 110. The pressure oil movesthe first and second pistons 74 and 75 to press the brake pads 76against the brake disc rotor 50, applying the braking force to the brakedisc rotor 50.

Referring to FIG. 4, the bicycle brake caliper assembly 100 isconfigured to be attached to the pipe portion 40 of the bicycle frame14. The disc brake caliper assembly 100 comprises the disc brake caliper110, the base member 120, a first thread bolt 141, and a second threadbolt 145. In the brake caliper 110 depicted in FIG. 4, parts other thanthe housing 112 (e.g., the brake pads 76 and the first and secondpistons 74 and 75) are omitted. The brake caliper 110 is coupled to thebase member 120 by the first thread bolt 141 and the second thread bolt145. The base member 120 is attached to the pipe portion 40 by the firstattaching member 151 and the second attaching member 155. The brakecaliper 110 and the base member 120 are made of metallic material suchas aluminum alloy or iron. One of the first attaching member 151 and thesecond attaching member 155 can be omitted from the disc brake caliper110 if needed and/or desired.

The base member 120 is configured to be coupled to the disc brakecaliper 110 and to be attached to the pipe portion 40 of the bicycleframe 14. More specifically, the base member 120 is configured to becoupled to the brake caliper 110 and to be attached to the bicycle frame14 (the pipe portion 40) such that relative position between therotational axis A1 of the brake disc rotor 50 and the brake caliper 110is adjustable in the radial direction D1 of the brake disc rotor 50.

The base member 120 extends in a longitudinal direction D3. Thelongitudinal direction D3 of the base member 120 is substantiallyparallel to the radial direction D1 of the brake disc rotor 50 in astate where the base member 120 is attached to the pipe portion 40 (FIG.1). Namely, the base member 120 extends in the radial direction D1 in astate where the base member 120 is attached to the pipe portion 40.

The base member 120 includes a main body 121, a first end portion 122,and a second end portion 123. In the first embodiment, the main body121, the first end portion 122, and the second end portion 123 areintegrally provided as a one piece unitary member. The main body 121 hasa plate shape and extends in the longitudinal direction D3 (in theradial direction D1). The first end portion 122 is opposite to thesecond end portion 123 with respect to the main body 121. The first endportion 122 is disposed at one end of the main body 121. The second endportion 123 is disposed at the other end of the main body 121. The basemember 120 includes a first attaching through-hole 124 and a secondattaching through-hole 125. The first attaching through-hole 124 isprovided at the first end portion 122. The second attaching through-hole125 is provided at the second end portion 123.

The base member 120 includes a caliper-side contact surface 128. Thecaliper-side contact surface 128 is flat and is provided on the mainbody 121. The caliper-side contact surface 128 is configured to contactthe brake caliper 110 in a state where the base member 120 is coupled tothe brake caliper 110.

The base member 120 further includes a coupling portion 131 at which thebrake caliper 110 is coupled. The coupling portion 131 includes a firstthrough-hole 132 and a second through-hole 136. The first through-hole132 and the second through-hole 136 are provided on the main body 121.The second through-hole 136 is arranged apart from the firstthrough-hole 132 in the radial direction D1 (in the longitudinaldirection D3). The second attaching through-hole 125 is spaced apartfrom the first attaching through-hole 124 in the radial direction D1 (inthe longitudinal direction D3). The first through-hole 132 and thesecond through-hole 136 are arranged between the first attachingthrough-hole 124 and the second attaching through-hole 125.

The first thread bolt 141 is configured to couple the brake caliper 110to the base member 120. The second thread bolt 145 is configured tocouple the brake caliper 110 to the base member 120. In FIG. 4, thefirst thread bolt 141 passes through the first through-hole 132 and thesecond thread bolt 145 passes through the second through-hole 136 in astate where the base member 120 is coupled to the brake caliper 110 withthe first thread bolt 141 and the second thread bolt 145. The firstthread bolt 141 is a countersunk head bolt and includes a first externalthread 142 and a first countersunk head 143. The second thread bolt 145is a countersunk head bolt and includes a second external thread 146 anda second countersunk head 147. In the first embodiment, the secondthread bolt 145 has substantially the same shape as that of the firstthread bolt 141. It should be understood that the second thread bolt 145has a shape different from that of the first thread bolt 141.

In a state where the base member 120 is coupled to the brake caliper 110with the first thread bolt 141 and the second thread bolt 145, the basemember 120 is attached to an attachment portion 41 of the pipe portion40 by the first attaching member 151 and the second attaching member155.

The attachment portion 41 of the pipe portion 40 is recessed andincludes a support surface 42, and threaded holes 43 and 44. The supportsurface 42 is configured to contact the base member 120. The threadedholes 43 and 44 are provided on the support surface 42. The base member120 is disposed within the attachment portion 41 in a state where thebase member 120 is attached to the pipe portion 40 with the firstattaching member 151 and the second attaching member 155.

The first attaching member 151 is a hexagon socket head bolt andincludes a first external thread 152 and a first hexagon socket head153. In FIG. 4, the first external thread 152 is screwed in the threadedhole 43 through the first attaching through-hole 124, and the first endportion 122 of the base member 120 is secured to the attachment portion41 of the pipe portion 40 with the first attaching member 151.

The second attaching member 155 is a hexagon socket head bolt andincludes a second external thread 156 and a second hexagon socket head157. In FIG. 4, the second external thread 156 is screwed in thethreaded hole 44 through the second attaching through-hole 125, and thesecond end portion 123 of the base member 120 is secured to theattachment portion 41 of the pipe portion 40 with the second attachingmember 155.

Referring to FIG. 5, the housing 112 of the brake caliper 110 includes aconnection port 115, a bleed port 116, a slit 114, and an attachmentsurface 119. Namely, the disc brake caliper 110 comprises the attachmentsurface 119. The connection port 115 and the bleed port 116 are in fluidcommunication with the caliper fluid passage 58 (FIG. 3). The hydraulicbrake hose 86 is connected with the connection port 115 via the banjo 87(FIG. 2). A bleed nipple (not shown) is coupled to the bleed port 116.The slit 114 extends such that an outer friction portion of the brakedisc rotor is disposed in the slit 114. The attachment surface 119 isflat and is configured to be contact the caliper-side contact surface128 (FIG. 4) of the base member 120 in a state where the brake caliper110 is coupled to the base member 120.

The disc brake caliper 110 comprises a first threaded hole 117 in whichthe first thread bolt 141 is to be inserted so as to couple the discbrake caliper 110 to one of the bicycle frame 14 and the base member 120attached to the bicycle frame 14. The first threaded hole 117 has athreaded portion that is at least partially provided at an internalcircumferential surface of the first threaded hole 117 so as to engagewith the first thread bolt 141. In the illustrated embodiment, the firstthread bolt 141 is inserted in the first threaded hole 117 so as tocouple the disc brake caliper 110 to the base member 120. The firstthread bolt 141 is configured to be inserted in the first threaded hole117 via the base member 120 so as to couple the base member 120 to thedisc brake caliper 110.

The disc brake caliper 110 further comprises a second threaded hole 118in which the second thread bolt 145 is to be inserted so as to couplethe disc brake caliper 110 to one of the bicycle frame 14 and the basemember 120. The second threaded hole 118 has a threaded portion that isat least partially provided at an internal circumferential surface ofthe second threaded hole 118 so as to engage with the second thread bolt145. In the illustrated embodiment, the second thread bolt 145 isinserted in the second threaded hole 118 so as to couple the disc brakecaliper 110 to the base member 120. The second thread bolt 145 isconfigured to be inserted in the second threaded hole 118 via the basemember 120 so as to couple the base member 120 to the disc brake caliper110. One of the first threaded hole 117 and the second threaded hole 118can be omitted from the disc brake caliper 110 if needed and/or desired.

As seen in FIG. 5, the first threaded hole 117 is provided on theattachment surface 119 of the housing 112. The second threaded hole 118is provided on the attachment surface 119 of the housing 112. In theillustrated embodiment, the attachment surface 119 comprises a singleflat surface on which the first threaded hole 117 and the secondthreaded hole 118 are provided. The attachment surface 119 can, however,includes a plurality of surfaces separated from each other. In theillustrated embodiment, the first threaded hole 117 has a first innerdiameter. The second threaded hole 118 has a second inner diameter equalto the first inner diameter. A distance between the first threaded hole117 and the second threaded hole 118 is substantially the same as adistance between the first through-hole 132 and the second through-hole136. In FIG. 5, the first external thread 142 of the first thread bolt141 is screwed in the first threaded hole 117, and the second externalthread 146 of the second thread bolt 145 is screwed in the secondthreaded hole 118.

The first threaded hole 117 has a first center axis A21. The secondthreaded hole 118 has a second center axis A22 parallel to the firstcenter axis A21. The first center axis A21 is non-parallel to themovement direction D4. The first center axis A21 of the first threadedhole 117 is parallel to a braking plane BP (FIG. 3) which isperpendicular to the movement direction D4. The second center axis A22of the second threaded hole 118 is parallel to the braking plane BP(FIG. 3). The braking plane BP can be defined based on a frictionsurface of the brake disc rotor 50, for example.

The second center axis A22 can be substantially parallel to the firstcenter axis A21 if needed and/or desired. The second center axis A22 canbe non-parallel to the first center axis A21 if needed and/or desired.At least one of the first center axis A21 and the second center axis A22can be substantially parallel to the braking plane BP if needed and/ordesired. At least one of the first center axis A21 and the second centeraxis A22 can be non-parallel to the braking plane BP if needed and/ordesired.

The base member 120 includes a frame-side contact surface 129 disposedon a side opposite to the brake caliper 110 with respect to the basemember 120. The frame-side contact surface 129 is flat and is providedon the main body 121, the first end portion 122, and the second endportion 123. The frame-side contact surface 129 is configured to contactthe support surface 42 (FIG. 4) of the pipe portion 40 in a state wherethe base member 120 is attached to the pipe portion 40.

As seen in FIG. 5, the first through-hole 132 includes a first taperedsurface 133 provided on the frame-side contact surface 129. The secondthrough-hole 136 includes a second tapered surface 137 provided on theframe-side contact surface 129. In a state where the base member 120 iscoupled to the brake caliper 110 with the first thread bolt 141, thefirst countersunk head 143 of the first thread bolt 141 contacts thefirst tapered surface 133 of the first through-hole 132 and is disposedwithin a space defined by the first tapered surface 133, preventing thefirst countersunk head 143 from protruding beyond the frame-side contactsurface 129 toward the pipe portion 40. In a state where the base member120 is coupled to the brake caliper 110 with the second thread bolt 145,the second countersunk head 147 of the second thread bolt 145 contactsthe second tapered surface 137 of the second through-hole 136 and isdisposed within a space defined by the second tapered surface 137,preventing the second countersunk head 147 from protruding beyond theframe-side contact surface 129 toward the pipe portion 40.

Referring to FIGS. 6A and 6B, the first through-hole 132 hassubstantially the same shape as that of the second through-hole 136. Thefirst tapered surface 133 has substantially the same shape as that ofthe second tapered surface 137. The first tapered surface 133 isprovided at an end portion of the first through-hole 132. The secondtapered surface 137 is provided at an end portion of the secondthrough-hole 136.

As seen in FIG. 6A, the first attaching through-hole 124 and the secondattaching through-hole 125 extend in a transverse direction D5 of thebase member 120. The transverse direction D5 is perpendicular to thelongitudinal direction D3 of the base member 120 and is defined alongthe caliper-side contact surface 128 and the frame-side contact surface129. The transverse direction D5 is substantially parallel to the axialdirection D2 of the brake disc rotor 50 in a state where the base member120 is attached to the pipe portion 40 of the bicycle frame 14. Namely,the first attaching through-hole 124 and the second attachingthrough-hole 125 extend in the axial direction D2 of the brake discrotor 50 in a state where the base member 120 is attached to the bicycleframe 14. Since the first attaching through-hole 124 and the secondattaching through-hole 125 extend in the axial direction D2, therelative position between the bicycle brake caliper assembly 100 and thebrake disc rotor 50 is adjustable in the axial direction D2. It shouldbe understood that the first attaching through-hole 124 and the secondattaching through-hole 125 can be circular through-holes.

Referring to FIG. 6B, a thickness of the first end portion 122 issubstantially the same as a thickness of the second end portion 123. Athickness T1 of the main body 121 is greater than a thickness T2 of thefirst end portion 122 and the second end portion 123.

Referring to FIG. 6C, a distance L11 between a center C11 of the firstattaching through-hole 124 and a center C12 of the first through-hole132 is different from a distance L12 between a center C14 of the secondattaching through-hole 125 and a center C13 of the second through-hole136. More specifically, the distance L11 between the center C11 of thefirst attaching through-hole 124 and the center C12 of the firstthrough-hole 132 is greater than the distance L12 between the center C14of the second attaching through-hole 125 and the center C13 of thesecond through-hole 136. The distances L11 and L12 are smaller than adistance L13 between the center C12 of the first through-hole 132 andthe center C13 of the second through-hole 136. Namely, the base member120 has an asymmetrical shape in the longitudinal direction D3. Sincethe distance L11 is different from the distance L12, turning upside downthe base member 120 can change a position of the coupling portion 131 inthe radial direction D1.

Referring to FIGS. 4 and 7, the base member 120 is attached to thebicycle frame 14 with one of a first orientation and a secondorientation. FIG. 4 illustrates the base member 120 that is disposed tobe attached to the pipe portion 40 with the first orientation. FIG. 7illustrates the base member 120 that is disposed to be attached to thepipe portion 40 with the second orientation.

As seen in FIG. 4, the first end portion 122 is disposed at an upperposition and the second end portion 123 is disposed at a lower positionin a state where the base member 120 is attached to the pipe portion 40with the first orientation. As seen in FIG. 7, the second end portion123 is disposed at an upper position and the first end portion 122 isdisposed at a lower position in a state where the base member 120 isattached to the pipe portion 40 with the second orientation. Namely, thebase member 120 disposed with the second orientation is upside-down inthe radial direction D1 with respect to the base member 120 disposedwith the first orientation.

As seen in FIG. 4, the first external thread 142 of the first threadbolt 141 is screwed in the first threaded hole 117 through the firstthrough-hole 132 and the second external thread 146 of the second threadbolt 145 is screwed in the second threaded hole 118 through the secondthrough-hole 136 in a state where the base member 120 is attached to thebicycle frame 14 with the first orientation. The first attaching member151 passes through the first attaching through-hole 124 to attach thebase member 120 to the bicycle frame 14. The second attaching member 155passes through the second attaching through-hole 125 to attach the basemember 120 to the bicycle frame 14. The first end portion 122 of thebase member 120 is secured to the attachment portion 41 of the pipeportion 40 with the first attaching member 151 and the threaded hole 43.The second end portion 123 of the base member 120 is secured to theattachment portion 41 of the pipe portion 40 with the second attachingmember 155 and the threaded hole 44.

As seen in FIG. 7, the first external thread 142 is screwed in the firstthreaded hole 117 through the second through-hole 136 and the secondexternal thread 146 is screwed in the second threaded hole 118 throughthe first through-hole 132 in a state where the base member 120 isattached to the bicycle frame 14 with the second orientation. The firstattaching member 151 passes through the second attaching through-hole125 to attach the base member 120 to the bicycle frame 14. The secondattaching member 155 passes through the first attaching through-hole 124to attach the base member 120 to the bicycle frame 14. The second endportion 123 of the base member 120 is secured to the attachment portion41 of the pipe portion 40 with the first attaching member 151 and thethreaded hole 43. The first end portion 122 of the base member 120 issecured to the attachment portion 41 of the pipe portion 40 with thesecond attaching member 155 and the threaded hole 44.

FIG. 8A is a side elevational view of the bicycle brake caliper assembly100 in a state where the base member 120 is attached to the pipe portion40 with the first orientation. FIG. 8B is a side elevational view of thebicycle brake caliper assembly 100 in a state where the base member 120is attached to the pipe portion 40 with the second orientation. FIG. 8Acorresponds to FIG. 4, and FIG. 8B corresponds to FIG. 7.

Referring to FIGS. 8A and 8B, the bicycle brake caliper assembly 100 canbe in two different states respectively corresponding to the brake discrotor 50 and a brake disc rotor 55 which has an outer diameter R2greater than an outer diameter R1 of the brake disc rotor 50. Morespecifically, the base member 120 is configured to be coupled to thebrake caliper 110 and to be attached to the bicycle frame 14 (the pipeportion 40) such that relative position between the rotational axis A1of the brake disc rotors 50 and 55 and the brake caliper 110 isadjustable in the radial direction D1 of the brake disc rotors 50 and55. The base member 120 is configured such that a first position P11 ofthe coupling portion 131 in a state where the base member 120 isattached to the bicycle frame 14 with the first orientation differs froma second position P12 of the coupling portion 131 in a state where thebase member 120 is attached to the bicycle frame 14 with the secondorientation, in the radial direction D1. In the first embodiment, thefirst and second positions P11 and P12 are defined on the basis of thesecond center axis A22 of the second threaded hole 118, for example.

As seen in FIG. 8A, a first distance L17 is defined between therotational axis A1 of the brake disc rotor 50 and the second center axisA22 of the second threaded hole 118 in the radial direction D1 in astate where the base member 120 is attached to the pipe portion 40 withthe first orientation. As seen in FIG. 8B, a second distance L18 isdefined between the rotational axis A1 of the brake disc rotor 55 andthe second center axis A22 of the second threaded hole 118 in the radialdirection D1 in a state where the base member 120 is attached to thepipe portion 40 with the second orientation. As seen in FIGS. 8A and 8B,the second distance L18 corresponding to the second orientation isgreater than the first distance L17 corresponding to the firstorientation. Accordingly, changing the orientation of the base member120 relative to the pipe portion 40 and the brake caliper 110 allows thebicycle brake caliper assembly 100 to be adjusted to each of the brakedisc rotors 50 and 55 having different outer diameters R1 and R2.

The base member 120 does not need to have the function which allows thedisc brake caliper assembly 100 to be adjusted to each of the brake discrotors 50 and 55 having different outer diameters R1 and R2. Forexample, in the base member 120 illustrated in FIG. 6C, the distance L11between the centers C11 and C12 can be equal to the distance L12 betweenthe centers C13 and C14. Furthermore, the base member 120 can be omittedfrom the disc brake caliper assembly 100 if needed and/or desired.

As seen in FIGS. 8A and 8B, the attachment surface 119 is configured toface the pipe portion 40 of the bicycle frame 14 in a state where thedisc brake caliper 110 is coupled to the bicycle frame 14. Theattachment surface 119 defines an end surface which faces the pipeportion 40 of the bicycle frame 14. The attachment surface 119 isdisposed between the first piston 74 and the pipe portion 40 in a statewhere the disc brake caliper 110 is mounted to the pipe portion 40.

The first piston 74 is disposed between the first center axis A21 andthe second center axis A22. The second piston 75 is disposed between thefirst center axis A21 and the second center axis A22 so as to at leastpartially face the first piston 74. The first piston 74 is disposedbetween the first center axis A21 and the second center axis A22 whenviewed from the movement direction D4. The second piston 75 is disposedbetween the first center axis A21 and the second center axis A22 so asto at least partially face the first piston 74 when viewed from themovement direction D4.

The first center axis A21 is non-parallel to the rotational axis A1 in astate where the disc brake caliper 110 is mounted to the bicycle frame14. The first center axis A21 of the first threaded hole 117 is parallelto the braking plane BP (FIGS. 3 and 5) which is perpendicular to therotational axis A1, in a state where the disc brake caliper 110 ismounted to the bicycle frame 14. The second center axis A22 of thesecond threaded hole 118 is parallel to the braking plane BP (FIGS. 3and 5), in a state where the disc brake caliper 110 is mounted to thebicycle frame 14.

As seen in FIGS. 8A and 8B, the first center axis A21 is non-parallel tothe rotational axis A1 in a state where the disc brake caliper 110 ismounted to the pipe portion 40 of the bicycle frame 14. The secondcenter axis A22 is non-parallel to the rotational axis A1 in a statewhere the disc brake caliper 110 is mounted to the pipe portion 40 ofthe bicycle frame 14.

Second Embodiment

A disc brake caliper assembly 200 in accordance with a second embodimentwill be described below referring to FIGS. 9 to 13. Elements havingsubstantially the same function as those in the first embodiment will benumbered the same here, and will not be described again in detail.

As seen in FIG. 9, the disc brake caliper assembly 200 is mounted to apipe portion 240 of the bicycle frame 14. In the illustrated embodiment,since the disc brake caliper assembly 200 is applied to a rear discbrake system, the pipe portion 240 of the bicycle frame 14 is a chainstay of the main frame 13, for example.

The disc brake caliper assembly 200 comprises a disc brake caliper 210.Unlike the disc brake caliper 110 in accordance with the firstembodiment, the base member 120 is omitted from the disc brake caliperassembly 200. The disc brake caliper 210 is directly mounted to the pipeportion 240 of the bicycle frame 14. An intermediate member such as thebase member 120 can, however, be applied to the disc brake caliper 210if needed and/or desired. The disc brake caliper 210 is for applying abraking force on a brake disc rotor 250 configured to be rotatable abouta rotational axis A3. The brake disc rotor 250 is rotatably supported bya bicycle hub assembly. Since the bicycle hub assembly and otherstructures around the brake disc rotor 250 are well known in the bicyclefield, they will not be described and/or illustrated in detail here forthe sake of brevity.

As seen in FIG. 10, the disc brake caliper 210 comprises the firstpiston 74. The first piston 74 is configured to be movable in themovement direction D4. The disc brake caliper 210 further comprises thesecond piston 75. The second piston 75 is configured to be movable inthe movement direction D4. The first piston 74 and the second piston 75are provided in a housing 212 of the disc brake caliper 210.

As seen in FIG. 11, the disc brake caliper 210 comprises an attachmentsurface 219 and a first threaded hole 217. The attachment surface 219and the first threaded hole 217 are provided on the housing 212. Theattachment surface 219 is configured to face the pipe portion 240 of thebicycle frame 14 in a state where the disc brake caliper 210 is coupledto the bicycle frame 14. The first threaded hole 217 is provided on theattachment surface 219. In the illustrated embodiment, the attachmentsurface 219 is configured to contact the pipe portion 240 in a statewhere the disc brake caliper 210 is coupled to the bicycle frame 14.

The disc brake caliper assembly 200 further includes a first thread bolt241. The first thread bolt 241 is to be inserted in the first threadedhole 217 so as to couple the disc brake caliper 210 to one of thebicycle frame 14 and a base member attached to the bicycle frame 14. Inthe illustrated embodiment, the first thread bolt 241 is inserted in thefirst threaded hole 217 so as to couple the disc brake caliper 210 tothe bicycle frame 14.

As seen in FIG. 11, the disc brake caliper 210 further comprises asecond threaded hole 218 and a second thread bolt 245. The secondthreaded hole 218 is provided on the housing 212. More specifically, thesecond threaded hole 218 is provided on the attachment surface 219 ofthe housing 212. The second thread bolt 245 is to be inserted so as tocouple the disc brake caliper 210 to one of the bicycle frame 14 and abase member. In the illustrated embodiment, the second thread bolt 245is inserted so as to couple the disc brake caliper 210 to the bicycleframe 14. In the illustrated embodiment, the second thread bolt 245 hassubstantially the same shape as that of the first thread bolt 241. Thesecond thread bolt 245 can, however, have a shape different from a shapeof the first thread bolt 241 if needed and/or desired.

The first threaded hole 217 has a first inner diameter. The secondthreaded hole 218 has a second inner diameter equal to the first innerdiameter. The second inner diameter of the second threaded hole 218 canbe different from the first inner diameter of the first threaded hole217 if needed and/or desired.

The first thread bolt 241 includes a first external thread 241 a and afirst head part 241 b. The first external thread 241 a is screwed in thefirst threaded hole 217. The second thread bolt 245 includes a secondexternal thread 245 a and a second head part 245 b. The second externalthread 245 a is screwed in the second threaded hole 218.

As seen in FIG. 11, the first threaded hole 217 has a first center axisA41. The first center axis A41 is non-parallel to the movement directionD4. The first center axis A41 is non-parallel to the rotational axis A3in a state where the disc brake caliper 210 is mounted to the bicycleframe 14 (more specifically, to the pipe portion 240 of the bicycleframe 14). The second threaded hole 218 has a second center axis A42parallel to the first center axis A41. The second center axis A42 isnon-parallel to the movement direction D4. The second center axis A42 isnon-parallel to the rotational axis A3 in a state where the disc brakecaliper 210 is mounted to the bicycle frame 14 (more specifically, tothe pipe portion 240 of the bicycle frame 14).

As seen in FIG. 10, the first center axis A41 of the first threaded hole217 is parallel to the braking plane BP which is perpendicular to themovement direction D4. The first center axis A41 of the first threadedhole 217 is parallel to the braking plane BP which is perpendicular tothe rotational axis A3, in a state where the disc brake caliper 210 ismounted to the bicycle frame 14.

The second center axis A42 of the second threaded hole 218 is parallelto the braking plane BP which is perpendicular to the movement directionD4. The second center axis A42 of the second threaded hole 218 isparallel to the braking plane BP, in a state where the disc brakecaliper 210 is mounted to the bicycle frame 14.

As seen in FIG. 11, the attachment surface 219 comprises a first portion264 and a second portion 266 divided from the first portion 264. In theillustrated embodiment, the first portion 264 is spaced apart from thesecond portion 266. The first threaded hole 217 is provided on the firstportion 264 of the attachment surface 219. The second threaded hole 218is provided on the second portion 266 of the attachment surface 219.

As seen in FIG. 12, the pipe portion 240 includes a first attachmenthole 268 and a second attachment hole 270. The first thread bolt 241extends through the first attachment hole 268 in a state where the discbrake caliper 210 is mounted to the pipe portion 240. The second threadbolt 245 extends through the second attachment hole 270 in a state wherethe disc brake caliper 210 is mounted to the pipe portion 240. In theillustrated embodiment, each of the first attachment hole 268 and thesecond attachment hole 270 is an elongated hole extending in the axialdirection D2.

As seen in FIG. 11, the pipe portion 240 includes a third attachmenthole 274 and a fourth attachment hole 272. The first thread bolt 241extends through the third attachment hole 274 in a state where the discbrake caliper 210 is mounted to the pipe portion 240. The second threadbolt 245 extends through the fourth attachment hole 272 in a state wherethe disc brake caliper 210 is mounted to the pipe portion 240. In theillustrated embodiment, each of the third attachment hole 274 and thefourth attachment hole 272 is an elongated hole extending in the axialdirection D2.

As seen in FIG. 12, the pipe portion 240 includes a support surface 276.In the illustrated embodiment, the support surface 276 includes a firstsupport surface 278 and a second support surface 280. The second supportsurface 280 is spaced apart from the first support surface 278. Thefirst attachment hole 268 is provided on the first support surface 278.The second attachment hole 270 is provided on the second support surface280.

The first support surface 278 is configured to face the first portion264 of the attachment surface 219. The second support surface 280 isconfigured to face the second portion 266 of the attachment surface 219.In the illustrated embodiment, the first support surface 278 isconfigured to contact the first portion 264 of the attachment surface219. The second support surface 280 is configured to contact the secondportion 266 of the attachment surface 219.

As seen in FIG. 13, the attachment surface 219 defines an end surfacewhich faces the pipe portion 240 of the bicycle frame 14. The attachmentsurface 219 is disposed between the first piston 74 and the pipe portion240 in a state where the disc caliper 210 is mounted to the pipe portion240.

The first piston 74 is disposed between the first center axis A41 andthe second center axis A42. The second piston 75 is disposed between thefirst center axis A41 and the second center axis A42 so as to at leastpartially face the first piston 74. In the illustrated embodiment, thefirst piston 74 is disposed between the first center axis A41 and thesecond center axis A42 when viewed from the movement direction D4. Thesecond piston 75 is disposed between the first center axis A41 and thesecond center axis A42 so as to at least partially face the first piston74 when viewed from the movement direction D4.

The term “comprising” and its derivatives, as used herein, are intendedto be open ended terms that specify the presence of the stated features,elements, components, groups, integers, and/or steps, but do not excludethe presence of other unstated features, elements, components, groups,integers and/or steps. This definition also applies to words of similarmeaning, for example, the terms “have”, “include” and their derivatives.

The terms “member”, “section,” “portion,” “part” or “element” when usedin the singular can have the dual meaning of a single part or aplurality of parts.

Finally, terms of degree such as “substantially”, “about” and“approximately” as used herein mean a reasonable amount of deviation ofthe modified term such that the end result is not significantly changed.

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

What is claimed is:
 1. A disc brake caliper for applying a braking forceon a brake disc rotor configured to be rotatable about a rotationalaxis, the disc brake caliper comprising: a first piston configured to bemovable in a movement direction; an attachment surface configured toface a pipe portion of a bicycle frame in a state where the disc brakecaliper is coupled to the bicycle frame; and a first threaded hole inwhich a first thread bolt is to be inserted so as to couple the discbrake caliper to one of the bicycle frame and a base member attached tothe bicycle frame, the first threaded hole being provided on theattachment surface, the first threaded hole having a first center axis,wherein the first threaded hole has a depth such that, when viewed in adirection parallel to the movement direction, a piston center axis isoffset by a distance from the first threaded hole in a directionparallel to the first center axis.
 2. The disc brake caliper accordingto claim 1, wherein the first threaded hole has a first center axiswhich is non-parallel to the rotational axis in a state where the discbrake caliper is mounted to the bicycle frame.
 3. The disc brake caliperaccording to claim 2, wherein the first center axis is parallel to abraking plane which is perpendicular to the rotational axis in a statewhere the disc brake caliper is mounted to the bicycle frame.
 4. Thedisc brake caliper according to claim 1, further comprising: a secondthreaded hole in which a second thread bolt is to be inserted so as tocouple the disc brake caliper to one of the bicycle frame and the basemember, the second threaded hole being provided on the attachmentsurface.
 5. The disc brake caliper according to claim 4, wherein theattachment surface defines an end surface which faces the pipe portionof the bicycle frame.
 6. The disc brake caliper according to claim 4,wherein the attachment surface comprises a single flat surface on whichthe first threaded hole and the second threaded hole are provided. 7.The disc brake caliper according to claim 4, wherein the attachmentsurface comprises a first portion and a second portion divided from thefirst portion, and the first threaded hole is provided on the firstportion of the attachment surface and the second threaded hole isprovided on the second portion of the attachment surface.
 8. The discbrake caliper according to claim 4, wherein the first threaded hole hasa first inner diameter, and the second threaded hole has a second innerdiameter equal to the first inner diameter.
 9. The disc brake caliperaccording to claim 4, wherein the first threaded hole has a first centeraxis which is non-parallel to the rotational axis in a state where thedisc brake caliper is mounted to the pipe portion of the bicycle frame.10. The disc brake caliper according to claim 9, wherein the firstcenter axis is parallel to a braking plane which is perpendicular to therotational axis in a state where the disc brake caliper is mounted tothe bicycle frame.
 11. The disc brake caliper according to claim 10,wherein the second threaded hole has a second center axis parallel tothe first center axis.
 12. The disc brake caliper according to claim 4,further comprising: a first piston, wherein the first threaded hole hasa first center axis, the second threaded hole has a second center axis,and the first piston is disposed between the first center axis and thesecond center axis.
 13. The disc brake caliper according to claim 12,further comprising: a second piston disposed between the first centeraxis and the second center axis so as to at least partially face thefirst piston.
 14. The disc brake caliper according to claim 13, whereinthe first center axis is non-parallel to the rotational axis in a statewhere the disc brake caliper is mounted to the pipe portion of thebicycle frame.
 15. The disc brake caliper according to claim 14, whereinthe first center axis is parallel to a braking plane which isperpendicular to the rotational axis in a state where the disc brakecaliper is mounted to the bicycle frame.
 16. The disc brake caliperaccording to claim 15, wherein the second center axis is parallel to thefirst center axis.
 17. A disc brake caliper comprising: a first pistonconfigured to be movable in a movement direction; and a first threadedhole in which a first thread bolt is to be inserted so as to couple thedisc brake caliper to one of a bicycle frame and a base member attachedto the bicycle frame, the first threaded hole having a first center axisnon-parallel to the movement direction, wherein the first threaded holehas a depth such that, when viewed in a direction parallel to themovement direction, a piston center axis is offset by a distance fromthe first threaded hole in a direction parallel to the first centeraxis.
 18. The disc brake caliper according to claim 17, wherein thefirst center axis is parallel to a braking plane which is perpendicularto the movement direction.
 19. The disc brake caliper according to claim17, further comprising: a second threaded hole in which a second threadbolt is to be inserted so as to couple the disc brake caliper to one ofthe bicycle frame and the base member, the second threaded hole having asecond center axis non-parallel to the movement direction.
 20. The discbrake caliper according to claim 19, wherein the first threaded hole hasa first inner diameter, and the second threaded hole has a second innerdiameter equal to the first inner diameter.
 21. The disc brake caliperaccording to claim 19, wherein the first piston is disposed between thefirst center axis and the second center axis.
 22. The disc brake caliperaccording to claim 21, further comprising: a second piston configured tobe movable in the movement direction and disposed between the firstcenter axis and the second center axis so as to at least partially facethe first piston.
 23. The disc brake caliper according to claim 22,wherein the first center axis is parallel to a braking plane which isperpendicular to the movement direction.
 24. The disc brake caliperaccording to claim 23, wherein the second center axis is parallel to thefirst center axis.
 25. A disc brake caliper assembly comprising: thedisc brake caliper according to claim 1 or 17; the base memberconfigured to be coupled to the disc brake caliper and to be attached tothe bicycle frame; and the first thread bolt configured to be insertedto the first threaded hole via the base member so as to couple the basemember to the disc brake caliper.